Which feature is primarily used for reading SD cards in devices like cameras?

The feature primarily used for reading SD cards in devices like cameras is the SD Card Slot. This specific slot is designed to accommodate SD cards, allowing users to easily insert and remove cards for reading and writing data. SD Card Slots are commonly found not just in cameras, but also in devices such as laptops and some tablets, providing a convenient method for transferring photos, videos, and other files directly from the card to the device.

In contrast, the USB 2.0 Port is generally used for connecting various peripherals, like external hard drives and USB flash drives, rather than for reading SD cards directly. An Optical Drive is designed for reading optical disc formats, such as CDs and DVDs, and does not accommodate SD cards at all. Daisychaining refers to the method of connecting multiple devices together in a series, typically associated with other kinds of connections, but it does not apply to the function of reading SD cards. Thus, the SD Card Slot is the specific feature designed for this purpose.